Chemicals, plastics and rubber industries

Study was conducted for adsorption of CO on nanosize Pd particles using density functional method and spectroscopically by means of infrared reflection absorption spectroscopy (IRAS) and sum frequency generation (SFG). The calculated results show that adsorption properties of rather small (111) and (001) cluster facets are similar to the properties of the corresponding ideal (infinite) Pd surfaces.

High-pressure CO adsorption on palladium(Pd)(111) is examined by X-ray photoelectron spectroscopy(XPS) and vibrational sum frequency generation (SFG) from 200 to 400 K, and in a pressure range from 10(super -6) to 1 mbar. Even in the millibar regime both methods indicated that CO adsorbed in "regular" adsorption sites such as hollow, bridge, and on-top.

A detailed comparative study of CO adsorption on two categories of oxide-supported palladium catalysts is discussed. The assignment of the CO vibrational frequencies to different types of sites on these systems has allowed a detailed structural characterization.